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Preparation and Characterization of Bis ( fluoroxy)perfluoroalkanes. 11. Bis (fluoroxy) perfluoromethane182 Phillip G. Thompson
Contribution No. 404 f r o m the Central Research Laboratories, Minnesota Mining and Manufacturing Company, St. Paul, Minnesota 55119. Received September 28,1966 Abstract: The preparation and characterization of the first member of the bis(fluoroxy)perfluoroalkanes, CF2(OF)2, are presented.
ady and co-workers were the first to report the C preparation of a carbon-containing hypofluorite, CF30F.4 Recently we have described a number of a
new carbon-containing -OF c o m p o u n d ~ . ~ ~These ~-~ include not only primary, secondary, and tertiary mono(fluoroxy)polyhaloalkanes and substituted derivatives thereof,+’ but also a new class of compounds, the bis(fluoroxy)perfluoroalkanes. In this paper the preparation, isolation, and identification of CF2(0F)2,the parent member of this class, are reported. Some physical and chemical properties of CF2(0F)* are also presented. Additional reactions will be reported later. Results and Discussion Bis(fluoroxy)perfluoromethane was first obtained in low yield by the direct fluorination of salts of trifluoroacetic acid. 0
II
Fz
CFsCONa +CFZ(OF)Z
Somewhat higher yields are obtained by the direct fluorination of sodium oxalate.* In both cases, the Fz
+
Na2CZO4+~CFZ(OF)Z 2NaF
reaction temperature and fluorine concentration were studied over wide ranges. The major factor in obtaining higher yields appears t o be control of the reaction so that excessive exotherms do not occur. Nonreactive solid diluents such as N a F have also been employed as described previ~usly,~ but their use does (1) Part I of this series: P. G. Thompson and J. H. Prager, J . Am. Chem. SOC.,in press. (2) This research was supported by the Advanced Research Projects Agency under Contract NOrd 18688 and was monitored by the Bureau of Naval Weapons. (3) The term “hypofluorite” is used to emphasize the -OF structural group in analogy to the universally recognized hypochlorite group -0C1, not to imply that the fluorine atom is positive relative to the oxygen atom. In accordance with the recommendations of the ACS Committee on Nomenclature of Highly Fluorinated Molecules, we have established the functional group name for the O F group as the fluoroxy group. (4) I
